Pneumatic tool.



No. 792,333. i PATENTED JUNE 13, 1905.

H. LEINBWEBER.

PNEUMATIG TOOL.

APPLICATION FILED NOV. 5, 1904.

UNITED STATES Patented Tune 13, 1905.

PATENT OEEICE.

HERMAN LEINEIVEBER, OF SOUTH CHICAGO, ILLINOIS, ASSIGNOR TO INTERNATIONAL TOOL COMPANY OF CHICAGO, OF CHICAGO, ILLI- NOIS, A CORPORATION OF ILLINOIS.

PNEUMATIC TOOL.

SPECIFICATION forming part of Letters Patent No. 792,333, dated June 13, 1905.

Application iled November 5, 1904:. Serial No. 231,491.

To t/f YL1/tom it may concern.-

Be it known that I, HERMAN LEINEWEBER, a citizen ot' the United States, residing at South Chicago, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Pneumatic Tools, oi' which the following is a specification.

My invention relates to an improvement in the class of valveless pneumatic tools in which the hammer is a piston contined in a casing to be reciprocated against the tool proper through the medium of Huid-pressure introduced against the piston alternately in opposite directions and exhausted on completing its work, the fluid-pressure being controllably introduced through the tool-handle from a suitable storage-supply; and it relates particularly to the construction of the means employed in conjunction with the handle for regulating the quantity of pressure introduced against the piston for actuating' it.

My object is to provide a novel and simple construction of valve mechanism in connection with the handle of the tool whereby the introduction oi' pressure to the piston may be regulated by the operator with his thumb against a controlling-lever to vary, while the tool is working, the amount of pressure undergoing such introduction, and thus regulate the force ot' the piston-stroke in accordance with thc requirements for the work being performed.

In the accompanying drawings, Figure lis a longitudinal section of a pneumatic tool provided with my improvements. Figs. 2, 3, 4, and 5 are sections taken, respectively, at the lines 2, 3, 4L, and 5 on Fig. l and viewed as indicated by arrows. Fig. 6 is a longitudinal section oi' the port-equipped valve-bushing; Fig. 7, a developed view of the valve, and Fig. 8 a plan View of the valve.

A is thc casing, having a desired tool B (shown broken) seated in one end, with its stem a projecting into an enlargement forming an air-chamber b in the casing. On the opposite end of the casing is secured a hollow head A', closed at its outer end, which is provided with an inner hollow central boss c to receive and cushion the piston C in its back stroke, this boss being within an enlargement in the head forming an air-cliamber (l. On the head is the handle, provided with the nipple E, to which is connected the iieXible tube (not shown) for -conducting air-pressure from any suitable source to the implement. An air-passage e of considerable width, as shown in Fig. 5, extends in the handle from the nipple through one side of the head to a port f in the casing, widened to cover a series of inlet-passages g therein, shown as live in number, and which lead lengthwise in the casingwall to an annular pressure-feeding chamber L therein. A plurality of exhaust-ports t' are shown radiating through the casingwall near the rear end of the piston, and similar exhaust-ports 7' are provided in the casing near the opposite end of the piston. The piston C, which is confined in the casing to reciprocate between the boss c and tool-stem a, is shown closed at both ends and contains a desired number of longitudinal ducts 7c, each terminating at its opposite ends, respectively, in lateral openings Z and on in the piston near its ends.

The foregoing description applies substantially to the pneumatic tool forming the subject of my application Jfor Letters Patent Serial No. 199,028 and is necessary for a ready understanding of the construction and operation ofthe valve mechanism on the handle which constitutes my present improvement and of which the following is a description.

In the handle is interposed in the passage e a cylindrical bore or housing n, into an annular enlargement in which, forming a chamber 0, the nipple leads. I/Vithin this housing is confined a tube or bushing p, provided between its ends with a circumferential series of elongated ports q and at its upper end with a port fr, coinciding with the inlet end to the air-passage e and of dimensions adapting it to cover' the latter. In the bushing p is a spring s, which is eoniined in the socket end of a cylindrical Valve t, reciprocably conned in the bushing p to be actuated in one direction by the spring and in the opposite direction by a thumb-lever o., fulcrumed in a recess e in the handle to engage one end of a rod yw, reciprocably confined in the handle to bear at its opposite end against the valve. About the valve t are formed in its surface a series of recesses ai, each shown by dotted lines in Fig. 8 to approximate a V shape in cross-section and leading to a port ;1/, extending toit in the valve-body from the outlet end of the latter', which normally bears against the inner end of the bore n. The recesses m in the series thereof about the valve and of which four are shown are disposed in step-like relation, the top and bottom of each being somewhat below the planes of the top and bottom of the one preceding it, but all being in an area within or conforming in height to the length of the ports Q, which are of uniform length. rIhe recesses and ports in the valve form pressureducts leading through it, with their inlet ends extending in different planes.

The operation is as follows, with the piston, to start with, bearing against the tool-stem c.' The operator holds in one hand the tool at the handle I), with his thumb against the lever u, slight pressure against which depresses the Valve t only enough to register the lowermost recess with the bushing-ports r] coinciding` with the chamber o, while increasing pressure will register therewith the next higher recess in succession, and so on until all the recesses register with. said bushing-ports to admit the full operating pressure lto the tool. The pressure flows from the chamber o, through the bushing-ports of one or more of the recesses fr; and ports gz/ in the valve and through the passage e, port f, and passages g, into the feeding-chamber 71 with which, in the position of the piston referred to, the openings Z register to admit the pressure through them, the piston-duets and the openings m. then registering with the chamber 7 into the latter, wherein it acts against the end of the piston therein and drives the piston backward until it passes the exhaust-ports .7', through which the pressure exhausts. The back stroke of the piston brings its openings m into registration with the feeding-chamber to admit pressure through them, the piston-ducts and the openings Z then registering with the chamber (Z into the latter', wherein it acts against the end ofthe piston therein and drives the piston against the stem a, permitting the pressure to exhaust through the ports v; as the piston passes them. In this manner the piston is reciprocated to act against the tool B.

It will be observed that the chamber d is larger than the chamber 7;. The purpose of this difference is to cause the air-pressure force for the forward piston-stroke to be greater th an that for producing the back stroke and to reduce to the minimum the recoil in the chamber (Z.

The valve mechanism with which the handle D is equipped affords most convenient means for regulating the force of the piston-stroke, which should be susceptible of moderation and increase for different kinds of work and for different parts of the same work. My improvement enables the operator by the pressure of his thumb to control the admission of pressure to the tool, and thereby to regulate to a nicety the force of the pistonstroke.

Obviously my improved regulating device may be used on pneumatic tools differing in construction from that shown and described and is therefore not intended to be limited to use with the latter, and it may be modilied in the details of its construction without departure from my invention.

What I claim as new, and desire to secure by Letters Patent, ism

l. In a pneumatic tool, the combination with a casing carrying at one end the tool and containing a reciproeable piston, of a handle provided with a passage through which to introduce air-pressure into the casing for actuating the piston, and pressure-regulating mechanism on the handle comprising a tube crossing said passage and provided with elongated ports registering therewith, a spring-pressed valve confined in said tube and having ducts leading through it with their inlet ends extending to diii'erent planes to be depressed successively into registration with said ports, and a lever fulerumed on the handle for operating said valve, substantially as and for the purpose set forth.

2. In a pneumatic tool, the combination with a casing carrying at one end the tool and containing a reciprocable piston, of a handle provided with a passage through which to introduce air-pressure into the casing for actuating the piston, and pressure-regulating mechanism on the handle comprising a tube crossing said passage and provided with elongated ports registering therewith, a spring-pressed valve confined in said tube, provided with a circuitous series of recesses disposed about it in step-like relation with ports leading from them to the outlet end of the valve, and a lever fulcrumed on the handle for operating said valve to register the recesses therein successively with said ports,'substantially as and for the purpose set forth.

3. In a pneumatic tool, the combination with a casing carrying at one end the tool and containing a reciprocable piston, of a handle provided with a passage through which to introduce air-pressure into the casing for actuating the piston, and pressure-regulating mechanism comprising a tubular housing in the handle crossing' said passage therein and provided with an annular chamber registering with said passage, a tubular bushing in said housing provided between its ends with elongated. ports registering with said chamber, a spring-pressed valve confined in said bushing and. having ducts leading through it with their IOO IIO

inlet ends extending to different planes to be depressed successively into registration with said ports, and a lever fulcrumed on the handle for operating said valve, substantially aS and for the purpose set forth.

4. In a pneumatic tool, the combination With a casing carrying at one end the tool and containing a reciprocable piston, of a handle provided with a passage through which to introduce air-pressure into the casing Jfor actuating the piston, and pressure-regulating mechanism comprising a tubular housing in the handle crossing said passage therein and provided With an annular chamber registering with said passage, a tubular bushing in said housing provided between its ends with elongated ports registering with said chamber, a spring-pressed valve coniined in said bushing, provided with a circuitous series of recesses disposed about it in step-like relation With ports leading from them to the outlet end of the valve, and a lever fulcrumed on the handle for operating said valve to register its recesses successively with said ports, substantially as and for the purpose set forth.

5. In a pneumatic tool, the combination With a casing carrying at one end the tool and containing a reciprocable piston, of a handle provided With a passage through which to introduce air-pressure into the casing for actuating the piston, and pressure-regulating meehanism comprising a tubular housing in the handle crossing said passage therein and provided With an annular chamber registering with said passage, a tubular bushing in said housing provided betweenits ends with acircuitous series of elongated ports registering with said chamber, a spring-pressed valve confined in said bushing, provided With a circuitous series of recesses disposed about it in steplike relation with ports leading from them to the outlet end of the valve, a rod reciprocably coniined in the handle to bear against said valve, and a thumb-lever fulcrumed on the handle and engaging said rod for operating the valve to register its recesses successively with said ports, substantially as and for the purpose set forth.

HERMAN LEINEVVEBER. In presence ofv- M. S. MACKENZIE, WV. B. DAvIEs. 

